from odoo import api, fields, models, _
from odoo.exceptions import ValidationError


class EducationLibraryFine(models.Model):
    _name = 'education.library.fine'
    _description = 'Library Fine'
    _rec_name = 'name'

    name = fields.Char(string='Reference', required=True, copy=False, readonly=True, default=lambda self: _('New'))
    issue_id = fields.Many2one('education.library.issue', string='Issue Record', required=True, ondelete='cascade')
    member_id = fields.Many2one('education.library.member', string='Member', required=True)
    student_id = fields.Many2one('education.student', string='Student')
    
    days_late = fields.Integer(string='Days Late', required=True)
    amount = fields.Float(string='Fine Amount', required=True)
    
    state = fields.Selection([
        ('draft', 'Draft'),
        ('assessed', 'Assessed'),
        ('paid', 'Paid'),
        ('waived', 'Waived'),
        ('cancelled', 'Cancelled')
    ], string='Status', default='draft', required=True)
    
    payment_reference = fields.Char(string='Payment Reference')
    paid_date = fields.Date(string='Paid Date')
    remarks = fields.Text(string='Remarks')

    @api.model_create_multi
    def create(self, vals_list):
        for vals in vals_list:
            if vals.get('name', _('New')) == _('New'):
                vals['name'] = self.env['ir.sequence'].next_by_code('education.library.fine') or _('New')
        return super().create(vals_list)

    @api.constrains('amount')
    def _check_amount(self):
        for record in self:
            if record.amount < 0:
                raise ValidationError(_('Negative fines are not permitted.'))

    def action_assess(self):
        self.write({'state': 'assessed'})

    def action_pay(self):
        for record in self:
            record.write({
                'state': 'paid',
                'paid_date': fields.Date.today()
            })

    def action_waive(self):
        self.write({'state': 'waived'})

    def action_cancel(self):
        self.write({'state': 'cancelled'})